Home / 1,420.20-2,128.28-553.50

Finding the Fourth Proportional to 1,420.20, 2,128.28 and 553.50

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Solution

The fourth proportional to 1,420.20, 2,128.28 and 553.50 is: 829.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,420.20 : 2,128.28 = 553.50 : x
  2. Step 2: Convert to fraction form
    1,420.20/2,128.28 = 553.50/x
  3. Step 3: Cross multiply
    1,420.20x = 2,128.28 × 553.50
  4. Step 4: Simplify right side
    1,420.20x = 1,178,000.21
  5. Step 5: Solve for x
    x = 1,178,000.21/1,420.20
  6. Step 6: Final answer
    x = 829.46

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.